As a method for imparting water/oil repellency to a surface of an article (such as a fiber product, etc.), a method of treating the article by using a water/oil repellent composition having dispersed in a liquid medium a copolymer having units based on a monomer having a polyfluoroalkyl group, is known. The article treated by using the water/oil repellent composition is required to have such a property (washing durability) that the water repellency is not lowered substantially even when subjected to washing repeatedly and a property (heavy-rain durability) that the water repellency is not lowered substantially even when exposed to heavy rainfall conditions.
As a water/oil repellent composition excellent in washing durability and heavy-rain durability, for example, the following water/oil repellent composition has been proposed.
(1) A water/oil repellent composition comprising a copolymer having units based on following monomer 1 and units based on the following monomer 2 (Patent Document 1),
Monomer 1: a (meth)acrylate having a C1-6 perfluoroalkyl group,
Monomer 2: a (meth)acrylate having a C20-30 alkyl group.
As water/oil repellent compositions excellent in antifouling properties and washing durability, for example, the following antifouling compositions have been proposed.
(2) An antifouling composition comprising a copolymer having units based on the following monomer 3, units based on the following monomer 4 and units based on the following monomer 5 (Patent Document 2).
Monomer 3: a (meth)acrylate having a C1-6 perfluoroalkyl group.
Monomer 4: a (meth)acrylate having a poly(oxyethylene) chain.
Monomer 5: a (meth)acrylate having a poly(oxyethylene-oxytetramethylene) chain.
(3) An antifouling composition comprising
a copolymer having units based on the following monomer 6, units based on the following monomer 7 and units based on the following monomer 8, wherein the proportion of fluorine atoms is at least 15 mass % and less than 45 mass %,
a copolymer having units based on the following monomer 6, units based on the following monomer 7 and units based on the following monomer 8, wherein the proportion of fluorine atoms is at least 45 mass %, and
a copolymer having units based on the following monomer 6, units based on the following monomer 9 and units based on the following monomer 10 (Patent Document 3).
Monomer 6: a (meth)acrylate having a C4-6 polyfluoroalkyl group,
Monomer 7: a (meth)acrylate having an alkyl group with at least 12 carbon atoms,
Monomer 8: vinyl chloride or vinylidene chloride,
Monomer 9: a (meth)acrylate having a poly(oxyethylene) chain.
Monomer 10: a (meth)acrylate having a poly(oxyethylene-oxytetramethylene) chain.